In the installation of rain gutters on a residential building, it is common to roll-form longitudinal sections of the gutter at the site of the building with each section corresponding to the length of an eave portion of the roof. This roll-forming minimizes the number of joints in the gutter and provides an attractive continuous appearance along the eave. Usually, the gutters are roll-formed from prefinisher or prepainted aluminum strip which is fed from a supply coil having a width corresponding to the periphery of the gutter. The continuous gutter is usually installed with longitudinally spaced brackets or aluminum anchor nails. The nails pierce holes within the outer and inner edge portions of the gutter and extend through spacer tubes into the vertical board and the ends of the supporting rafters.
There have been many different types of perforated screens and nonperforated or impervious cover devices which are designed to cover ether all or a large portion of the gutters to avoid collecting within the gullets leaves, sticks, bark and other debris which are carried down the roof by rain water. For example, U.S. Pat. Nos. 2,672,832, 4,435,925, 4,455,791, 4,796,390 and 4,866,890 disclose various forms of solid or impervious gutter cover members. The members are mounted above the gutters and project under the roof covering or shingles for directing water flowing from the shingles into the gullet and for deflecting leaves and other debris onto the outer edge or return flange portion of the gutter. For example, the gutter cover disclosed in connection with FIG. 7 of U.S. Pat. No. 4,455,791 is formed of sheet metal or aluminum and has a longitudinally extending rolled or curled outer edge portion. The edge portion is spaced inwardly and above the outer edge portion or return flange portion of the gutter by a series of longitudinally spaced sheet metal brackets. The brackets grip the curled outer edge portion of the gutter cover and also grip the top return flange or the outer edge portion of the gutter to form a gap between the opposing edge portions. Water flowing across the gutter cover is directed partially around the rounded edge portion of the gutter by surface adhesion and falls downwardly through the gap into the gutter.
One objection to impervious-type gutter covers as disclosed in the above-mentioned patents, is that leaves, small sticks, small pieces of bark and other debris which are directed from the gutter cover onto the outer edge portion of the gutter, flow downwardly along the outer exposed surface of the gutter and drop from the bottom wall of the gutter. As a result, dirt collects on the outer exposed surface of the gutter and results in a gutter having an undesirable dirty appearance after a period of use, especially when the gutter is roll-formed from white finished aluminum strip. In addition, it has been found that the longitudinally spaced brackets which mount on the outer return flange portion of the gutter to support and space the curled outer edge portion of the cover, are awkward to install and sometimes shift inwardly or drop off after being installed for a period of time so that the outer edge portion of the cover is not properly spaced from the outer edge portion of the gutter. Also, the outer edge portion of the gutter is usually not perfectly straight so that the gap varies along the length of the gutter and may be too wide or too narrow.